| /** @file |
| * @brief IPv4 IGMP related functions |
| */ |
| |
| /* |
| * Copyright (c) 2021 Intel Corporation |
| * |
| * SPDX-License-Identifier: Apache-2.0 |
| */ |
| |
| #include <logging/log.h> |
| LOG_MODULE_DECLARE(net_ipv4, CONFIG_NET_IPV4_LOG_LEVEL); |
| |
| #include <errno.h> |
| #include <net/net_core.h> |
| #include <net/net_pkt.h> |
| #include <net/net_stats.h> |
| #include <net/net_context.h> |
| #include <net/net_mgmt.h> |
| #include <net/igmp.h> |
| #include "net_private.h" |
| #include "connection.h" |
| #include "ipv4.h" |
| #include "net_stats.h" |
| |
| /* Timeout for various buffer allocations in this file. */ |
| #define PKT_WAIT_TIME K_MSEC(50) |
| |
| #define IPV4_OPT_HDR_ROUTER_ALERT_LEN 4 |
| |
| static const struct in_addr all_systems = { { { 224, 0, 0, 1 } } }; |
| static const struct in_addr all_routers = { { { 224, 0, 0, 2 } } }; |
| |
| #define dbg_addr(action, pkt_str, src, dst) \ |
| NET_DBG("%s %s from %s to %s", action, pkt_str, \ |
| log_strdup(net_sprint_ipv4_addr(src)), \ |
| log_strdup(net_sprint_ipv4_addr(dst))); |
| |
| #define dbg_addr_recv(pkt_str, src, dst) \ |
| dbg_addr("Received", pkt_str, src, dst) |
| |
| static int igmp_v2_create(struct net_pkt *pkt, const struct in_addr *addr, |
| uint8_t type) |
| { |
| NET_PKT_DATA_ACCESS_DEFINE(igmp_access, |
| struct net_ipv4_igmp_v2_report); |
| struct net_ipv4_igmp_v2_report *igmp; |
| |
| igmp = (struct net_ipv4_igmp_v2_report *) |
| net_pkt_get_data(pkt, &igmp_access); |
| if (!igmp) { |
| return -ENOBUFS; |
| } |
| |
| igmp->type = type; |
| igmp->max_rsp = 0U; |
| net_ipaddr_copy(&igmp->address, addr); |
| igmp->chksum = 0; |
| igmp->chksum = net_calc_chksum_igmp((uint8_t *)igmp, sizeof(*igmp)); |
| |
| if (net_pkt_set_data(pkt, &igmp_access)) { |
| return -ENOBUFS; |
| } |
| |
| return 0; |
| } |
| |
| static int igmp_v2_create_packet(struct net_pkt *pkt, const struct in_addr *dst, |
| const struct in_addr *group, uint8_t type) |
| { |
| const uint32_t router_alert = 0x94040000; /* RFC 2213 ch 2.1 */ |
| int ret; |
| |
| ret = net_ipv4_create_full(pkt, |
| net_if_ipv4_select_src_addr( |
| net_pkt_iface(pkt), |
| dst), |
| dst, |
| 0U, |
| 0U, |
| 0U, |
| 0U, |
| 1U); /* TTL set to 1, RFC 3376 ch 2 */ |
| if (ret) { |
| return -ENOBUFS; |
| } |
| |
| /* Add router alert option, RFC 3376 ch 2 */ |
| if (net_pkt_write_be32(pkt, router_alert)) { |
| return -ENOBUFS; |
| } |
| |
| net_pkt_set_ipv4_opts_len(pkt, IPV4_OPT_HDR_ROUTER_ALERT_LEN); |
| |
| return igmp_v2_create(pkt, group, type); |
| } |
| |
| static int igmp_send(struct net_pkt *pkt) |
| { |
| int ret; |
| |
| net_pkt_cursor_init(pkt); |
| net_ipv4_finalize(pkt, IPPROTO_IGMP); |
| |
| ret = net_send_data(pkt); |
| if (ret < 0) { |
| net_stats_update_ipv4_igmp_drop(net_pkt_iface(pkt)); |
| net_pkt_unref(pkt); |
| return ret; |
| } |
| |
| net_stats_update_ipv4_igmp_sent(net_pkt_iface(pkt)); |
| |
| return 0; |
| } |
| |
| static int send_igmp_report(struct net_if *iface, |
| struct net_ipv4_igmp_v2_query *igmp_v2_hdr) |
| { |
| struct net_if_ipv4 *ipv4 = iface->config.ip.ipv4; |
| struct net_pkt *pkt = NULL; |
| int i, count = 0; |
| int ret = 0; |
| |
| if (!ipv4) { |
| return -ENOENT; |
| } |
| |
| for (i = 0; i < NET_IF_MAX_IPV4_MADDR; i++) { |
| if (!ipv4->mcast[i].is_used || !ipv4->mcast[i].is_joined) { |
| continue; |
| } |
| |
| count++; |
| } |
| |
| if (count == 0) { |
| return -ESRCH; |
| } |
| |
| for (i = 0; i < NET_IF_MAX_IPV4_MADDR; i++) { |
| if (!ipv4->mcast[i].is_used || !ipv4->mcast[i].is_joined) { |
| continue; |
| } |
| |
| pkt = net_pkt_alloc_with_buffer(iface, |
| IPV4_OPT_HDR_ROUTER_ALERT_LEN + |
| sizeof(struct net_ipv4_igmp_v2_report), |
| AF_INET, IPPROTO_IGMP, |
| PKT_WAIT_TIME); |
| if (!pkt) { |
| return -ENOMEM; |
| } |
| |
| /* TODO: send to arbitrary group address instead of |
| * all_routers |
| */ |
| ret = igmp_v2_create_packet(pkt, &all_routers, |
| &ipv4->mcast[i].address.in_addr, |
| NET_IPV4_IGMP_REPORT_V2); |
| if (ret < 0) { |
| goto drop; |
| } |
| |
| ret = igmp_send(pkt); |
| if (ret < 0) { |
| goto drop; |
| } |
| |
| /* So that we do not free the data while it is being sent */ |
| pkt = NULL; |
| } |
| |
| drop: |
| if (pkt) { |
| net_pkt_unref(pkt); |
| } |
| |
| return ret; |
| } |
| |
| enum net_verdict net_ipv4_igmp_input(struct net_pkt *pkt, |
| struct net_ipv4_hdr *ip_hdr) |
| { |
| NET_PKT_DATA_ACCESS_CONTIGUOUS_DEFINE(igmp_access, |
| struct net_ipv4_igmp_v2_query); |
| struct net_ipv4_igmp_v2_query *igmp_hdr; |
| |
| /* TODO: receive from arbitrary group address instead of |
| * all_systems |
| */ |
| if (!net_ipv4_addr_cmp_raw(ip_hdr->dst, (uint8_t *)&all_systems)) { |
| NET_DBG("DROP: Invalid dst address"); |
| return NET_DROP; |
| } |
| |
| igmp_hdr = (struct net_ipv4_igmp_v2_query *)net_pkt_get_data(pkt, |
| &igmp_access); |
| if (!igmp_hdr) { |
| NET_DBG("DROP: NULL IGMP header"); |
| return NET_DROP; |
| } |
| |
| if (net_calc_chksum_igmp((uint8_t *)igmp_hdr, |
| sizeof(*igmp_hdr)) != 0U) { |
| NET_DBG("DROP: Invalid checksum"); |
| goto drop; |
| } |
| |
| net_pkt_acknowledge_data(pkt, &igmp_access); |
| |
| dbg_addr_recv("Internet Group Management Protocol", &ip_hdr->src, |
| &ip_hdr->dst); |
| |
| net_stats_update_ipv4_igmp_recv(net_pkt_iface(pkt)); |
| |
| (void)send_igmp_report(net_pkt_iface(pkt), igmp_hdr); |
| |
| net_pkt_unref(pkt); |
| |
| return NET_OK; |
| |
| drop: |
| net_stats_update_ipv4_igmp_drop(net_pkt_iface(pkt)); |
| |
| return NET_DROP; |
| } |
| |
| static int igmp_send_generic(struct net_if *iface, |
| const struct in_addr *addr, |
| bool join) |
| { |
| struct net_pkt *pkt; |
| int ret; |
| |
| pkt = net_pkt_alloc_with_buffer(iface, |
| IPV4_OPT_HDR_ROUTER_ALERT_LEN + |
| sizeof(struct net_ipv4_igmp_v2_report), |
| AF_INET, IPPROTO_IGMP, |
| PKT_WAIT_TIME); |
| if (!pkt) { |
| return -ENOMEM; |
| } |
| |
| ret = igmp_v2_create_packet(pkt, &all_routers, addr, |
| join ? NET_IPV4_IGMP_REPORT_V2 : NET_IPV4_IGMP_LEAVE); |
| if (ret < 0) { |
| goto drop; |
| } |
| |
| ret = igmp_send(pkt); |
| if (ret < 0) { |
| goto drop; |
| } |
| |
| return 0; |
| |
| drop: |
| net_pkt_unref(pkt); |
| |
| return ret; |
| } |
| |
| int net_ipv4_igmp_join(struct net_if *iface, const struct in_addr *addr) |
| { |
| struct net_if_mcast_addr *maddr; |
| int ret; |
| |
| maddr = net_if_ipv4_maddr_lookup(addr, &iface); |
| if (maddr && net_if_ipv4_maddr_is_joined(maddr)) { |
| return -EALREADY; |
| } |
| |
| if (!maddr) { |
| maddr = net_if_ipv4_maddr_add(iface, addr); |
| if (!maddr) { |
| return -ENOMEM; |
| } |
| } |
| |
| ret = igmp_send_generic(iface, addr, true); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| net_if_ipv4_maddr_join(maddr); |
| |
| net_if_mcast_monitor(iface, &maddr->address, true); |
| |
| net_mgmt_event_notify_with_info(NET_EVENT_IPV4_MCAST_JOIN, iface, |
| &maddr->address.in_addr, |
| sizeof(struct in_addr)); |
| return ret; |
| } |
| |
| int net_ipv4_igmp_leave(struct net_if *iface, const struct in_addr *addr) |
| { |
| struct net_if_mcast_addr *maddr; |
| int ret; |
| |
| maddr = net_if_ipv4_maddr_lookup(addr, &iface); |
| if (!maddr) { |
| return -ENOENT; |
| } |
| |
| if (!net_if_ipv4_maddr_rm(iface, addr)) { |
| return -EINVAL; |
| } |
| |
| ret = igmp_send_generic(iface, addr, false); |
| if (ret < 0) { |
| return ret; |
| } |
| |
| net_if_ipv4_maddr_leave(maddr); |
| |
| net_if_mcast_monitor(iface, &maddr->address, false); |
| |
| net_mgmt_event_notify_with_info(NET_EVENT_IPV4_MCAST_LEAVE, iface, |
| &maddr->address.in_addr, |
| sizeof(struct in_addr)); |
| return ret; |
| } |